Oil Motion Control by an Extra Pinning Structure in Electro-Fluidic Display
<p>Working illustration of an electro-fluidic device (EFD). (<b>a</b>) OFF state without voltage; (<b>b</b>) ON state with a certain voltage.</p> "> Figure 2
<p>(<b>a</b>–<b>g</b>): Schematic diagram of the fabrication process of electro-fluidic displays; (<b>h</b>,<b>j</b>) are the top view images of the lithography masks of one pixel with (<b>j</b>) or without (<b>h</b>) extra pinning structure (EPS) design; (<b>i</b>): illustration of the pixels with central EPS design.</p> "> Figure 3
<p>Pixel with different EPS distributions. The center of the pixel is chosen as the origin for the <span class="html-italic">x</span>, <span class="html-italic">y</span> axes. We use the value of (<span class="html-italic">x</span>,<span class="html-italic">y</span>) to describe the actual (measured) position of the EPS in μm. (<b>A</b>) the baseline case without EPS; (<b>B</b>–<b>E</b>) EPS with different locations.</p> "> Figure 4
<p>Oil motion control by EPS (<b>a</b>) DC driving waveform (5 Hz) with 100 ms pulse (<b>b</b>) pixel open states of different EPS distributions with increasing applied voltage.</p> "> Figure 5
<p>White area percentage (WA) at different applied voltages for pixels with different EPS designs. The aperture of nine pixels (3 × 3) was monitored for each sample. The error bar shows standard deviation (<span class="html-italic">σ</span>) in WA.</p> "> Figure 6
<p>Comparison of optical response of pixel switching on process for base line pixel without EPS (<b>A</b>) and pixels with different EPS distributions (<b>B</b>,<b>C</b>,<b>D</b>,<b>E</b>), applied voltage = 30 V.</p> "> Figure 7
<p>Comparison of optical response of pixel switching off process for base line pixel without EPS (<b>A</b>) and pixels with different EPS distributions (<b>B</b>,<b>C</b>,<b>D</b>,<b>E</b>), applied voltage = 0 V.</p> "> Figure 8
<p>Voltage-dependent switching process of baseline pixels (<b>a</b>,<b>b</b>) and D-type pixels with off diagonal EPS (<b>c</b>,<b>d</b>). Inserted are the oil motion states in one pixel captured by high-speed camera.</p> ">
Abstract
:1. Introduction
2. Materials and Methods
2.1. Chemicals and Materials
2.2. Preparation of Electro-Fluidic Display with or without Pinning Structure
2.3. Oil Motion Observation
3. Results and Discussions
3.1. Characterization of Pixel Structures Combined with An EPS
3.2. Optical Control by Pinning Structure
3.2.1. EPS Guided Oil Motion during Pixel Switching-On
3.2.2. EPS Influence on Pixel Aperture Ratio
3.3. Response Time
3.3.1. Effect of EPS Location on Pixel Response
3.3.2. Applied Voltage Dependent Pixel Response
4. Conclusions
5. Patents
Acknowledgments
Author Contributions
Conflicts of Interest
References
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No. | A | B | C | D | E |
---|---|---|---|---|---|
EPS distribution | |||||
Oil rupture states |
No. | EPS Distributions | Oil Rupture Time (ms) | Response Time (ms) | Off Time (ms) |
---|---|---|---|---|
A | 2.0 ± 0.0 | 23.5 ± 1.9 | 10.0 ± 0.1 | |
B | 5.1 ± 0.3 | 21.7 ± 1.0 | 8.6 ± 0.2 | |
C | 2.2 ± 0.3 | 10.9 ± 1.5 | 8.3 ± 0.3 | |
D | 1.2 ± 0.3 | 7.3 ± 0.5 | 10.2 ± 0.6 | |
E | 1.6 ± 0.2 | 8.6 ± 0.7 | 8.2 ± 0.6 |
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Dou, Y.; Tang, B.; Groenewold, J.; Li, F.; Yue, Q.; Zhou, R.; Li, H.; Shui, L.; Henzen, A.; Zhou, G. Oil Motion Control by an Extra Pinning Structure in Electro-Fluidic Display. Sensors 2018, 18, 1114. https://doi.org/10.3390/s18041114
Dou Y, Tang B, Groenewold J, Li F, Yue Q, Zhou R, Li H, Shui L, Henzen A, Zhou G. Oil Motion Control by an Extra Pinning Structure in Electro-Fluidic Display. Sensors. 2018; 18(4):1114. https://doi.org/10.3390/s18041114
Chicago/Turabian StyleDou, Yingying, Biao Tang, Jan Groenewold, Fahong Li, Qiao Yue, Rui Zhou, Hui Li, Lingling Shui, Alex Henzen, and Guofu Zhou. 2018. "Oil Motion Control by an Extra Pinning Structure in Electro-Fluidic Display" Sensors 18, no. 4: 1114. https://doi.org/10.3390/s18041114